# CVE-2026-100227: Apache CXF: XML Signature wrapping in JAX-RS XML Security

> Attackers can bypass XML signature verification in Apache CXF by wrapping signed documents in unsigned content, tricking applications into trusting malicious data.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 9 Oct 2026
- **Updated:** 15 Oct 2026
- **Also known as:** CLEANSTART-2026-JA94279, GHSA-m89p-3qw6-fh4r

## What is CVE-2026-100227?

CVE-2026-100227 is a high-severity vulnerability in Apache Cxf, published on 9 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Improper Verification of Cryptographic Signature vulnerability in Apache CXF's JAX-RS XML Security module. The JAX-RS XML Signature interceptors (XmlSigInHandler, XmlSigInInterceptor and the streaming XmlSecInInterceptor) did not ensure that the XML passed to the application was covered by the signature. An attacker with any document signed by a trusted key could wrap it in unsigned content, which the application would then treat as signed.
Users are recommended to upgrade to versions 4.2.4 or 4.1.9 or 3.6.13, which fix this issue.

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2026-100227?

It affects 1 product.


Products: Apache Cxf.

## How do I fix CVE-2026-100227?

Upgrade to a fixed version.

## Is CVE-2026-100227 being exploited?

There is no known exploitation of CVE-2026-100227 in the wild and no public exploit code.

## Other vulnerabilities in Apache Cxf

- [CVE-2012-2379](https://insights.sbomify.com/CVE-2012-2379/): XML Signature/Encryption Not Validated in Apache CXF (critical 10.0)
- [CVE-2026-66909](https://insights.sbomify.com/CVE-2026-66909/): Apache CXF: Unsafe deserialization of inbound JMS ObjectMessage (critical 9.8)
- [CVE-2026-68079](https://insights.sbomify.com/CVE-2026-68079/): Apache CXF: DefaultEncryptingCodeDataProvider allows unlimited authorization code replay (critical 9.8)
- [CVE-2026-50628](https://insights.sbomify.com/CVE-2026-50628/): Apache CXF: OAuth2: Inverted IP Binding Check Defeats Security Control (critical 9.8)
- [CVE-2025-48913](https://insights.sbomify.com/CVE-2025-48913/): Apache CXF: Untrusted JMS configuration can lead to RCE (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-100227 and fix it if it is affected.

What it is: CVE-2026-100227 is a high-severity vulnerability in Apache Cxf, published on 9 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-100227 in the wild and no public exploit code.

Affected product: Apache Cxf. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-100227/ (Markdown: https://insights.sbomify.com/CVE-2026-100227/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-100227
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-100227
- OSV: https://osv.dev/vulnerability/CVE-2026-100227

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-100227/
Summaries are generated and may contain mistakes; the official description above is the record.